Baseline Quality-of-Life of Caregivers of Patients With Heart Failure Prior to Advanced Therapies: Findings From the Sustaining Quality of Life of the Aged: Transplant or Mechanical Support (SUSTAIN-IT) Study.

BACKGROUND: We compared health-related quality of life (HRQOL), depressive symptoms, anxiety, and burden in caregivers of older patients with heart failure based on the intended therapy goal of the patient: awaiting heart transplantation (HT) with or without mechanical circulatory support (MCS) or prior to long-term MCS; and we identified factors associated with HRQOL. METHODS: Caregivers (n = 281) recruited from 13 HT and MCS programs in the United States completed measures of HRQOL (EQ-5D-3L), depressive symptoms (PHQ-8), anxiety (STAI-state), and burden (Oberst Caregiving Burden Scale). Analyses included ANOVA, Kruskal-Wallis tests, χ2 tests, and linear regression. RESULTS: The majority of caregivers were female, white spouses with ≤ 2 comorbidities, median [Q1,Q3] age = 62 [57.8, 67.0] years. Caregivers (HT with MCS = 87, HT without MCS = 98, long-term MCS = 96) reported similarly high baseline HRQOL (EQ-5D-3L visual analog scale median score = 90; P = 0.67 for all groups) and low levels of depressive symptoms. STAI-state median scores were higher in the long-term MCS group vs the HT groups with and without MCS, (38 vs 32 vs 31; P < 0.001), respectively. Burden (task: time spent/difficulty) differed significantly among groups. Caregiver factors (number of comorbidities, diabetes and higher anxiety levels) were significantly associated with worse caregiver HRQOL, R2 = 26%. CONCLUSIONS: Recognizing caregiver-specific factors, including comorbidities and anxiety, associated with the HRQOL of caregivers of these older patients with advanced HF may guide support strategies.

ATP release during cell swelling activates a Ca2+-dependent Cl- current by autocrine mechanism in mouse hippocampal microglia.

Microglia cells, resident immune cells of the brain, survey brain parenchyma by dynamically extending and retracting their processes. Cl- channels, activated in the cellular response to stretch/swelling, take part in several functions deeply connected with microglia physiology, including cell shape changes, proliferation, differentiation and migration. However, the molecular identity and functional properties of these Cl- channels are largely unknown. We investigated the properties of swelling-activated currents in microglial from acute hippocampal slices of Cx3cr1 +/GFP mice by whole-cell patch-clamp and imaging techniques. The exposure of cells to a mild hypotonic medium, caused an outward rectifying current, developing in 5-10 minutes and reverting upon stimulus washout. This current, required for microglia ability to extend processes towards a damage signal, was carried mainly by Cl- ions and dependent on intracellular Ca2+. Moreover, it involved swelling-induced ATP release. We identified a purine-dependent mechanism, likely constituting an amplification pathway of current activation: under hypotonic conditions, ATP release triggered the Ca2+-dependent activation of anionic channels by autocrine purine receptors stimulation. Our study on native microglia describes for the first time the functional properties of stretch/swelling-activated currents, representing a key element in microglia ability to monitor the brain parenchyma.

Splicing factors differentially expressed in psoriasis alter mRNA maturation of disease-associated EDA+ fibronectin.

The EDA+ fibronectin splicing variant is overexpressed in psoriatic non-lesional epidermis and sensitizes keratinocytes to mitogenic signals. However, regulation of its abundance is only partially understood. In our recent cDNA microarray experiment, we identified three SR-rich splicing factors-splicing factor, arginine/serine-rich 18 (SFRS18), peptidyl-prolyl cis-trans isomerase G (PPIG), and luc-7 like protein 3 (LUC7L3)-which might be implicated in the preactivated states of keratinocytes in psoriatic non-involved skin and could also contribute to the regulation of fibronectin mRNA maturation. In this study, we investigated the role of LUC7L3, PPIG, and SFRS18 in psoriasis and in the mRNA maturation process of fibronectin. Regarding tissue staining experiments, we were able to demonstrate a characteristic distribution of the splicing factors in healthy, psoriatic non-involved and involved epidermis. Moreover, the expression profiles of these SR-rich proteins were found to be very similar in synchronized keratinocytes. Contribution of splicing facwwtors to the EDA+ fibronectin formation was also confirmed: their siRNA silencing leads to altered fibronectin mRNA and protein expression patterns, suggesting the participation in the EDA domain inclusion. Our results indicate that LUC7L3, PPIG, and SFRS18 are not only implicated in EDA+ fibronectin formation, but also that they could possess multiple roles in psoriasis-associated molecular abnormalities.

Report From the American Society of Transplantation Conference on Donor Heart Selection in Adult Cardiac Transplantation in the United States.

Cardiac transplantation remains the only definitive treatment for end-stage heart failure. Transplantation rates are limited by a shortage of donor hearts. This shortage is magnified because many hearts are discarded because of strict selection criteria and concern for regulatory reprimand for less-than-optimal posttransplant outcomes. There is no standardized approach to donor selection despite proposals to liberalize acceptance criteria. A donor heart selection conference was organized to facilitate discussion and generate ideas for future research. The event was attended by 66 participants from 41 centers with considerable experience in cardiac donor selection. There were state-of-the-art presentations on donor selection, with subsequent breakout sessions on standardizing the process and increasing utilization of donor hearts. Participants debated misconceptions and established agreement on donor and recipient risk factors for donor selection and identified the components necessary for a future donor risk score. Ideas for future initiatives include modification of regulatory practices to consider extended criteria donors when evaluating outcomes and prospective studies aimed at identifying the factors leading to nonacceptance of available donor hearts. With agreement on the most important donor and recipient risk factors, it is anticipated that a consistent approach to donor selection will improve rates of heart transplantation.

An engineered U1 small nuclear RNA rescues splicing defective coagulation F7 gene expression in mice.

BACKGROUND: The ability of the spliceosomal small nuclear RNA U1 (U1snRNA) to rescue pre-mRNA splicing impaired by mutations makes it an attractive therapeutic molecule. Coagulation factor deficiencies due to splicing mutations are relatively frequent and could therefore benefit from this strategy. However, the effects of U1snRNAs in vivo remain unknown. OBJECTIVES: To assess the rescue of the F7 c.859+5G>A splicing mutation (FVII+5A), causing severe human factor VII (hFVII) deficiency, by the modified U1snRNA+5a (U1+5a) in a murine model. METHODS: Mice expressing the human F7 c.859+5G>A mutant were generated following liver-directed expression by plasmid or recombinant adeno-associated viral (AAV) vector administration. The rescue of the splice-site defective pre-mRNA by U1+5a was monitored in liver and plasma through hFVII-specific assays. RESULTS: Injection of plasmids encoding the U1+5a rescued plasma hFVII levels, which increased from undetectable to ~8.5% of those obtained with the wild-type hFVII plasmid control. To assess long-term effects, mice were injected with low and high doses of two AAV vectors encoding the FVII+5A splice site mutant as template to be corrected by U1+5a. This strategy resulted in hFVII plasma levels of 3.9 ± 0.8 or 23.3 ± 5.1 ng mL⁻¹ in a dose-dependent manner, corresponding in patients to circulating FVII levels of ~1-4.5% of normal. Moreover, in both experimental models, we also detected correctly spliced hFVII transcripts and hFVII-positive cells in liver cells. CONCLUSIONS: Here we provide the first in vivo proof of-principle of the rescue of the expression of a splicing-defective F7 mutant by U1snRNAs, thus highlighting their therapeutic potential in coagulation disorders.

Effects of recombinant follicle-stimulating hormone on bone turnover markers in infertile women undergoing in vitro fertilization procedure.

CONTEXT: There is experimental but limited clinical evidence that FSH may have direct effects on bone. OBJECTIVE: The aim of the study was to evaluate the effects of acute FSH stimulation on bone turnover in premenopausal women. DESIGN AND SETTING: We conducted a prospective study at a referral center. PATIENTS: Twenty-nine infertile women (age range, 30-40 yr) undergoing an in vitro fertilization procedure were included in the study. INTERVENTIONS: Pharmacological suppression of endogenous gonadotropin and estradiol (E2) production by GnRH analog (leuprolide 1 mg/d s.c.) was followed by stimulation with recombinant FSH (rFSH; starting dose, 375 IU/d s.c.). MAIN OUTCOME MEASURES: We measured serum osteocalcin, C-telopeptides of type-1 collagen (ß-CTX), FSH, and E2 at the beginning of leuprolide administration (T0), at the beginning of rFSH administration (T1), and 3 d (T2) and 10 d (T3) after the first dose of rFSH. RESULTS: At T1, the suppression of FSH and E2 secretion, as an effect of leuprolide administration, led to a significant increase in serum ß-CTX values vs. T0 (P < 0.001). After the administration of rFSH, a rapid increase in serum FSH was observed, whereas serum E2 values increased more slowly. At T2, the increase in serum FSH values above our reference range for early follicular phase (with E2 in the reference range) did not induce any significant change in median serum ß-CTX values as compared to T1. At T3 (when both FSH and E2 were high), serum ß-CTX values decreased significantly vs. T1 (P < 0.001). Osteocalcin did not change significantly throughout the study period. CONCLUSIONS: Our model suggests that FSH does not acutely exert relevant direct effects on bone metabolism in premenopausal women.

A selective cytopheretic inhibitory device for use during cardiopulmonary bypass surgery.

BACKGROUND: Systemic inflammatory response syndrome (SIRS) can occur in association with cardiopulmonary bypass (CPB) surgery, resulting in multiple organ dysfunction (MOD). Activated neutrophils have been implicated as major inciting factors in this process. Neutrophil-depleting filters incorporated within the extracorporeal blood circuit during CPB have been developed and evaluated, with inconsistent clinical results. METHODS: A novel, biomimetic, selective cytopheretic device (SCD) was tested in vitro within a blood circuit to assess safety and interactions with blood components and further evaluated ex vivo in a bovine model of CPB surgery during ventricular assist device implantation. RESULTS: In vitro blood circuit studies demonstrated that the SCD reduces circulating neutrophils while maintaining low rates of hemolysis compared to current leukocyte-reduction filters. In the bovine CPB model, animals without SCD treatment (No SCD) demonstrated an increase in circulating white blood cell (WBC) and neutrophil counts, steadily increasing throughout CPB. SCD with only systemic heparin anticoagulation (SCD-H) acutely reduced neutrophils for the first 2 hrs of CPB, but followed with a greater than 6-fold increase in neutrophil counts. SCD treatment with regional citrate anticoagulation along the SCD circuit (SCD-C) reduced systemic neutrophil counts throughout 4 hrs of CPB despite lower amounts of eluted cells from the SCD. When analyzed for immature neutrophils, the control and SCD-H showed increasing counts at later time-points, not seen in the SCD-C group, suggesting a more complex mechanism of action than simple leukoreduction. CONCLUSIONS: These results suggest that SCD-C therapy may disrupt the systemic leukocyte response during CPB, leading to improved outcomes for CPB-mediated MOD.

Detection of a rare CDKN2A intronic mutation in a Hungarian melanoma-prone family and its role in splicing regulation.

BACKGROUND: The major locus for melanoma predisposition is the cell cycle regulatory CDKN2A gene on chromosome 9p21. However, the frequency of germline coding mutations of the CDKN2A gene is lower than expected in melanoma-prone families linked to chromosome 9p21. OBJECTIVES: To investigate whether the rare IVS1+37 G/C intronic mutation of the CDKN2A gene, recently identified in a Hungarian melanoma-prone family, influences mRNA splicing regulation. METHODS: CDKN2A minigenes containing the wild-type and the mutant intronic sequence were created and transfected into HeLa cells with the aim of studying the mRNA transcripts. RESULTS: The results revealed the emergence of a differential splicing pattern from the wild-type and the mutant minigene, suggesting that this mutation may alter the splicing of CDKN2A primary mRNA and therefore might have a pathogenetic role in familial melanoma. CONCLUSIONS: We believe that these results confirm the importance of the identification and characterization of CDKN2A intronic mutations with a view to improving our understanding of the pathogenesis, and explain why the frequency of germline coding mutations of the CDKN2A gene is lower than expected in melanoma-prone families linked to chromosome 9p21.

Long-term use of the CentriMag® Ventricular Assist System as a right ventricular assist device: a case report.

Right ventricular failure (RVF) following implantation of a left ventricular assist system (LVAS) is associated with high morbidity and mortality.( 1-4 ) Numerous centers have reported short-term use of the CentriMag (®) Ventricular Assist System (CVAS) (Levitronix LLC, Waltham, MA) for treatment of cardiogenic shock, decompensated heart failure and right ventricular failure (RVF) following LVAS implantation.( 5-9 ) The present report reviews the clinical course of a patient requiring long-term right ventricular support utilizing the CVAS, following a HeartMate (®) II LVAS (Thoratec Corp. Pleasanton, CA) implantation. Elevated cytotoxic antibody levels complicated the patient's treatment plan by precluding orthotropic heart transplantation. The CVAS operated for 304 days without mechanical difficulty until replaced with the HeartWare (®) Ventricular Assist System (HeartWare Inc. Miramar, FL).

RNA-based therapeutic approaches for coagulation factor deficiencies.

Substitutive therapy has significantly ameliorated the quality of life of patients with coagulation factor deficiencies. However, there are some limitations that support research towards alternative therapeutic approaches. Here we focus on the rescue of coagulation factor biosynthesis by targeting the RNA processing and translation, which would permit restoration of the altered gene expression while maintaining the gene regulation in the physiological tissues. The essential prerequisite of the three reported RNA-based correction approaches (i-iii), which rely on mutation types and are applicable even to large size mRNAs, is the presence in cells of the precursor (pre-mRNA) or mature mRNA forms. (i) In the F7 gene, modification of the small nuclear RNA U1 (U1 snRNA), the key component of the spliceosomal U1 ribonucleoprotein, re-directs correct usage of a mutated exon-intron junction, triggering synthesis of correct mRNA and secretion of functional factor (F)VII. (ii) Spliceosome-mediated RNA trans-splicing (SMaRT) between mutated and engineered pre-mRNAs produces normal FVIII mRNA and secretion of functional protein. (iii) Aminoglycoside drugs induce ribosome readthrough and suppress premature translation termination caused by nonsense mutations in FVII, VIII and IX. The rescued expression levels ranged from very low (aminoglycosides) to moderate (U1 snRNA and SMaRT), which could result in amelioration of the disease phenotypes. These findings prompt further studies aimed at demonstrating the clinical translatability of RNA-based strategies, which might open new avenues in the treatment of coagulation factor deficiencies.

First American experience with the Terumo DuraHeart left ventricular assist system.

Since the first implantation of a left ventricular assist system (LVAS) 45 years ago, LVAS therapy has emerged as a viable option for the treatment of advanced heart failure. The current generation of LVASs in clinical evaluation has design features enabling longer and more reliable support durations. We describe the operating characteristics of the DuraHeart LVAS (Terumo Heart, Inc., Ann Arbor, MI). The DuraHeart LVAS is a magnetically-levitated centrifugal pump that began a FDA-approved clinical trial for evaluation of bridge to transplant indication in July of 2008. Magnetic levitation of the spinning-pump impeller is hypothesized to improve long-term mechanical reliability and biological compatibility of the pump. Other design features make the DuraHeart LVAS particularly suited for implantation without cardiopulmonary bypass (CPB). A description of the implant procedure for the first six American implants of the DuraHeart LVAS both on-CPB and off-CPB, including CPB techniques employed, are discussed. While it is still very early in the DuraHeart LVAS experience, the initial outcomes of the first six patient implants would suggest that the device is a safe and effective LVAS.

In vitro and in vivo pharmacological role of TLQP-21, a VGF-derived peptide, in the regulation of rat gastric motor functions.

BACKGROUND AND PURPOSE: Vgf gene expression has been detected in various endocrine and neuronal cells in the gastrointestinal tract. In this study we investigated the pharmacological activity of different VGF-derived peptides. Among these, TLQP-21, corresponding to the 556-576 fragment of the protein was the unique active peptide, and its pharmacological profile was further studied. EXPERIMENTAL APPROACH: The effects of TLQP-21 were examined in vitro by smooth muscle contraction in isolated preparations from the rat gastrointestinal tract and, in vivo, by assessing gastric emptying in rats. Rat stomach tissues were also processed for immunohistochemical and biochemical characterization. KEY RESULTS: In rat longitudinal forestomach strips, TLQP-21 (100 nmol x L(-1)-10 micromol x L(-1)) concentration-dependently induced muscle contraction (in female rats, EC(50) = 0.47 micromol.L(-1), E(max): 85.7 +/- 7.9 and in male rats, 0.87 micromol x L(-1), E(max): 33.4 +/- 5.3; n = 8), by release of prostaglandin (PG)E(2) and PGF(2a) from the mucosal layer. This effect was significantly antagonized by indomethacin and selective inhibitors of either cyclooxygenase-1 (S560) or cyclooxygenase-2 (NS398). Immunostaining and biochemical studies confirmed the presence of VGF in the gastric neuronal cells. TLQP-21, injected i.c.v. (2-32 nmol per rat), significantly decreased gastric emptying by about 40%. This effect was significantly (P < 0.05) blocked by i.c.v. injection of indomethacin, suggesting that, also in vivo, this peptide acts in the brain stimulating PG release. CONCLUSIONS AND IMPLICATIONS: The present results demonstrate that this VGF-derived peptide plays a central and local role in the regulation of rat gastric motor functions.

Sympathectomy alters bone architecture in adult growing rats.

Sympathetic nervous system (SNS) fibres and alpha- and beta-receptors are present in bone, indicating that the SNS may participate in bone metabolism. The importance of these observations is controversial because stimulation or inhibition of the SNS has had various effects upon both anabolic and catabolic activity in this tissue. In this study we evaluated the effects of pharmacological sympathectomy, using chronic treatment of maturing male rats with 40 mg of guanethidine/kg i.p., upon various parameters in bone. Double labelling with tetracycline injection was also performed 20 and 2 days before sacrifice. Bone mass, mineral content, density and histomorphometric characteristics in different skeletal regions were determined. Bone metabolic markers included urinary deoxypyridinoline and serum osteocalcin measurements. Guanethidine significantly reduced the accretion of lumbar vertebral bone and of mineral content and density, compared to controls. Femoral bone mineral content and density were also significantly reduced, compared to controls. Histomorphometric analyses indicated these effects were related to a reduction of cortical bone and mineral apposition rate at femoral diaphysials level. Both markers of bone metabolism were reduced in controls as they approached maturity. Guanethidine significantly decreased serum osteocalcin compared to controls, while urinary deoxypyridinoline was unchanged. These data indicate that guanethidine-induced sympathectomy caused a negative balance of bone metabolism, leading to decreased mass by regulating deposition rather than resorption during modeling and remodeling of bone.

Central ghrelin gastroprotection involves nitric oxide/prostaglandin cross-talk.

BACKGROUND AND PURPOSE: Ghrelin, a gut-brain peptide, is considered a gastroprotective factor in gastric mucosa. We investigated the role of prostaglandins (PG) and the possible interplay between PGs and nitric oxide (NO) in ghrelin gastroprotection against ethanol (EtOH)-induced gastric lesions. EXPERIMENTAL APPROACH: We examined the effects of (1) central ghrelin (4 mug per rat) injection on PGE(2) accumulation in normal or EtOH-lesioned gastric mucosa, (2) pretreatment with indomethacin (10 mg kg(-1), p.o.), a non-selective cyclooxygenase (COX) inhibitor, and with a selective COX-1, SC560 (5 mg kg(-1), p.o.) or COX-2 inhibitor, celecoxib (3.5 mg kg(-1), p.o.) on ghrelin gastroprotection against 50% EtOH (1 mL per rat)-induced gastric lesions, (3) the NO synthase inhibitor, L-NAME (70 mg kg(-1), s.c), on gastric PGE(2) content in ghrelin-treated rats and (4) central ghrelin on the expression of constitutive and inducible NOS and COX mRNA and on the localization of the immunoreactivity for COX-2 in the gastric mucosa exposed to EtOH. KEY RESULTS: Ghrelin increased PGE(2) in normal mucosa, whereas, it reversed the EtOH-induced PGE(2) surge. Ghrelin had no effect on mucosal COX-1 expression but reduced the EtOH-induced increase in COX-2 expression and immunoreactivity. Indomethacin and SC560, but not celecoxib, removed ghrelin gastroprotection. L-NAME prevented the PGE(2) surge induced by ghrelin and, like indomethacin, reduced EtOH-induced PGE(2) increase. Ghrelin enhanced eNOS expression and reduced iNOS mRNA. CONCLUSIONS AND IMPLICATIONS: This study shows that COX-1-derived PGs are mainly involved in ghrelin gastroprotection and that the constitutive-derived NO together with PGE(2) are involved in ghrelin gastroprotective activity.

Heart and lung transplantation in the United States, 1997-2006.

This article highlights trends in heart and lung transplantation between 1997 and 2006, drawing on data from the OPTN and SRTR. The total number of candidates actively awaiting heart transplantation declined by 45% over the last decade, dropping from 2414 patients in 1997 to 1327 patients in 2006. The overall death rates among patients awaiting heart transplantation declined over the same period. The distribution of recipients among the different status groups at the time of heart transplantation changed little between the inception of the new classification system in 1999 and 2005. Deaths in the first year after heart transplantation have steadily decreased. At the end of 2006, 2885 candidates were awaiting a lung transplant, up 10% from the 1997 count. The median time-to-transplant for listed patients decreased by 87% over the decade, dropping from 1053 days in 1997 to 132 days in 2006. Selection for listing and transplantation has shifted toward more urgent patients since the May 2005 implementation of a new lung allocation system based on survival benefit and urgency rather than waiting time. Only 31 heart-lung transplants were performed in 2006, down from a high of 62 in 1997.

Role of biochemical markers of bone remodeling in clinical practice.

Bone tissue is subject to remodeling throughout the lifetime of an individual. Through a continuous remodeling cycle, actuated via the so-called 'bone remodeling units', old bone is resorbed by osteoclasts with the formation of cavities that are subsequently filled by osteoblasts. Bone loss observed in old age and in women after menopause is due to an imbalance between bone resorption and formation. Biochemical markers provide a dynamic view of the remodeling process, which covers rate of turnover and pathogenesis, and should improve fracture risk prediction. Furthermore, they can be used to monitor the short-term effects of therapy, and indicate if an excessive slowing of the remodeling process is occurring. When searching for markers of bone remodeling, biochemists have focused mainly on skeletal molecules that can be dosed in plasma and/or urine, as indicators of osteoblast function (i.e. bone alkaline phosphatase, osteocalcin, procollagene I C- and N-terminal propeptides) or osteoclast function (i.e. pyridinium crosslinks, collagen I C- and N-terminal telopeptides). The clinical significance of any marker for bone remodeling depends on two fundamental characteristics: specificity and variability. If the objective is to monitor therapeutic efficacy, it seems most rational to use a resorption marker for drugs that act principally on osteoclast, such as estrogens or bisphosphonates, while for drugs that act principally on osteoblast, such as PTH-peptides a marker for bone formation would be more appropriate.

Results from a multicenter evaluation of the 4th generation Elecsys Troponin T assay.

BACKGROUND AND OBJECTIVE: Discrepancies between serum and heparin plasma samples have been described for many commercial troponin assays including the cardiac troponin T (cTnT) assay. Using the current 3rd generation Elecsys Troponin T immunoassay, heparin plasma cannot be recommended for the determination of cTnT due to systematic lower test results caused by a direct interference of the immunoassay by heparin. The purpose of the multicenter study was to evaluate the analytical performance of an improved 4th generation Elecsys Troponin T immunoassay with a special focus on the comparability of cTnT results determined in heparin plasma and serum. METHODS AND RESULTS: The multicenter evaluation was performed in 10 clinical laboratories according to a standardized protocol (Roche Diagnostics, Penzberg, Germany, Study No. B05P008). The Elecsys Troponin T immunoassay was performed on the Modular Analytics E170 and Elecsys 2010 systems. Intraassay imprecision (n = 21) and total imprecision (2 runs/d, 10 days, triplicate measurements) were evaluated using 2 commercial controls (Roche Diagnostics) and 6 different serum pools (cTnT: 0.0140 - 4.102 microg/L). Intraassay CVs ranged from 0.73 to 3.22%. Total imprecision CVs ranged from 3.61 to 35.45% (cTnT < 0.1 microg/L) and 1.82 to 9.09% (cTnT > 0.1 microg/L), respectively. The cut-off for myocardial necrosis was determined to be 0.03 microg/L using the 10% total imprecision CV criteria. Linearity was assessed by serial dilutions of 6 different serum samples using cTnT negative serum pools. Linearity was proven up to 21.3 microg/L (recoveries: 90% - 110%). Regression data of all comparison studies were calculated according to the method of Passing and Bablok. The method comparison between the 4th generation and the commercially available cTnT immunoassay showed highly similar results across the whole measuring range (0.01 - 25.0 microg/L): y = 1.024x -0.001, r = 0.998; n = 988. Using the commercially available cTnT reagent, the serum to heparin plasma comparison yielded a systematic bias to approximately 8% lower cTnT results in heparin plasma. However, suitable comparability was obtained using the 4th generation Elecsys cTnT assay. The regression analysis (serum vs. heparin plasma) across the studied measuring range (cTnT: 0.01 - 14 microg/L) yielded the following equation: y = 0.975x + 0.001; r = 0.986; n = 403. However, rare individual serum to matched heparin plasma samples still yielded poor comparability (deviation > 20%) using the 4th generation Elecsys Troponin T immunoassay. CONCLUSION: Our data confirm an excellent analytical performance of the improved troponin T immunoassay. Most importantly, no systematic bias between cTnT results determined in serum and heparin plasma was observed from data obtained in 7 evaluation sites. The performance of the 4th generation Elecsys Troponin T assay is therefore comparable to other commercially available troponin immunoassays. Further studies are necessary to investigate the cause of poor comparability of cTnT results in rare individual serum to matched heparin plasma samples.

Ticlopidine prevents the formation but delays the healing of ethanol-induced gastric lesions in the rat.

The effects of acute or long-term oral ticlopidine administration in normal rat gastric mucosa or on gastric lesions induced by ethanol 50% (EtOH, 1 ml/rat, os) were examined and compared with those of acetylsalicylic acid (ASA). Ticlopidine does not affect gastric mucosal integrity either after acute (100 and 300 mg kg(-1)) or 1-week (100 mg kg(-1), die) oral administration. Ticlopidine (30-300 mg kg(-1), os) administered 1h before EtOH dose-dependently prevented the development of gastric haemorragic lesions. When ticlopidine was administered 1h after EtOH, it significantly (p<0.05) delays gastric lesions healing. Acute ASA (50 and 100 mg kg(-1), os) administration causes a mild irritant activity similar to that observed after 1 week of ASA (50 mg kg(-1), os/die) administration. In condition of mucosal damage, ASA does not modify either the induction or the healing of EtOH-induced gastric lesions. To assess the possible involvement of endogenous nitric oxide (NO) or prostaglandins (PG) in the gastric protective activity of ticlopidine, the rats were pretreated with an inhibitor of NO-synthesis, L-NAME (70 mg kg(-1), s.c.) or the inhibitor of PG synthesis, indomethacin (Indo, 10 mg kg(-1), s.c.). Indo, but not L-NAME, was able to significantly counteract the gastroprotective activity of ticlopidine against EtOH injury. Furthermore, ticlopidine increases (47%) gastric PGE(2) content in normal mucosa compared to the one detected in control rats, thus suggesting that endogenous PGs contribute to enhanced mucosal resistance by ticlopidine. These results indicate that ticlopidine exerts dual effects during the development and healing of gastric lesions induced by EtOH.